[Sephora]

So we have been in our Colonial type house for 4 years this month. We do not have C/A so rely on windows open, ceiling fans and window unit AC for the warm/hot months here in CT.

It gets VERY VERY hot upstairs when it is hot outside. We have a toddler and an infant now so I can't bare the thought of them sleeping up there when it is so hot. And I get scared with 3 window units running all at the same time all night long (hello electric bill and don't want to bust a fuse).

Anyways, someone asked me if we had an attic. I said yes and then they asked if we had an attic fan and I know WE DO NOT. They said that if we had one it would prob help a lot with it getting so hot on the second level.

What do you think? I mean it makes sense.

So where do we go about getting one and where do we put it and if we did get one how would we turn it off and on?

I believe from the outside you can see "vents" at the top of the house. This is good right? The fan would go in front of this, correct?

Thanks for any insight or help!

 

[hvac122]

Attic fans are a terrible investment. Most attics are not ventillated near enough for these high CFM fans. With this being the case the air you paid to condition will be drawn from your living area. It could also cause negitive pressure safety issues. I highly recommend that people stay away from them and if they have one we ask them to disable it.

If you don't want to add central air then use the window shakers and if your worried about the electrical then have a electrician out to check it for you.

 

[handy man88]

Before installing an attic fan, make sure your soffits are louvered and there are openings on the edge of your roof that will allow proper air flow.

I've actually seen new homes built with 4-5 attic fans installed.

For those looking to be eco friendly, check this out. It pretty much does away with any fears of electrical fires/issues, and you can probably get a tax break.

http://www.costco.com/Browse/Product.aspx?Prodid=11270027&search=attic%20fan&Mo=0&cm_re=1_en-_-Top_Left_Nav-_-Top_search&lang=en-US&Nr=P_CatalogName:BC&Sp=S&N=5000043&whse=BC&Dx=mode+matchallpartial&Ntk=Text_Search&Dr=P_CatalogName:BC&Ne=4000000&D=attic%20fan&Ntt=attic%20fan&No=0&Ntx=mode+matchallpartial&Nty=1&topnav=&s=1

 

[Scuba_Dave]

I'm installing an attic fan in a walk up attic
It's a great investment installed properly
You can buy them at most big box or hardware stores
You do need to make sure that it is not overpowered for your ventilation
Mine will be on a thermostat AND a manual switch
Turned on late at night after it cools off it will suck all the hot air out & cool the attic off
With cooling the house off at night we very rarely need to use our AC's
It's MUCH cheaper to use a fan then an AC
Usually an attic fan is thru the roof exhaust or out a gable vent

What venting do you have in the attic?
What insulation in the attic floor/ceiling?

Solar powered - more $$ - no electric bill
Only runs during the day

Thru the roof unit, had one at my last house

Gable vent

 

[hvaclover]

HEY DAVE!

don't look now but that flying saucer from the Twilight Zone with the tiny people inside landed on your house!!!!

 

[Scuba_Dave]

Yeah, but they are friendly :laughing:

I actually just picked up one of the flying saucers from someone for free
Brand new off of craigslist
I also have a gable/attic fan

Now I dunno what I'm going to do

I may hook-up the gable fan in the garage as a fan for the summer
Install the other one in the attic to vent thru the cupola

 

[hvaclover]

Don't believe in them my self. Unless the attic is hermetically sealed from the living space it will cause a higher infiltration rate. That'll put more heat into the home.

 

[Scuba_Dave]

I think most are overpowered
People buy a unit that is too big for the venting
If I lived in a hot/humid climate I'd probably pass
But in our area it helps to cool the house at night

I suppose if there are enough window fans - pointed out - they could pull hot air into the house from the attic. I usually point more fans going into the house then going out

My last house had very poor attic venting. Very poor insulation in a flat roof, closed up the hosue could go up to 90+. So the attic fan made a huge difference to cool the house off

 

[milender]

Hi, just to throw in my two cents, the attic fans I've seen have been placed in the ceiling of a hallway for instance, blowing air into the attic, pulling in cool air from slightly open windows, usually used at night. They have louvers and close when shut off. I've seen them in the big box stores, and are about 24 X 24 in size.

 

[handy man88]

Hi, just to throw in my two cents, the attic fans I've seen have been placed in the ceiling of a hallway for instance, blowing air into the attic, pulling in cool air from slightly open windows, usually used at night. They have louvers and close when shut off. I've seen them in the big box stores, and are about 24 X 24 in size.

These are called whole house fans.

 

[mjbxx]

Just curious, if a roof had a ridge vent with adequate soffit vents, would you need an attic fan? I live in north eastern NC with high humidity in the summer.

 

[Scuba_Dave]

A properly vented roof air circulates as the air heats up
--heat/hot air rises, cool air is drawn in from lower vents
Once the sun goes down that circulation slows down

In many cases being able to turn a fan on & continue the cooling at a faster rate can let the attic cool down faster

The problem is that in hotter areas you could be pulling AC cooled air out of the house up thru the attic. Then more hot humid air enters your house. I'm in New England - MA - very little AC use & not usually humid all that much

 

[mjbxx]

It would probably be wise to forgo utilizing an attic fan in my humid climate.

 

[Sephora]

As I stated in my OP, I live in Connecticut. It gets war/hot during the summer months and it gets humid as times. For the rest of the year, it is pretty nice.

I believe there are vents on each side of the attic but I would have to double check. I have never been in my attic as right now we don't have ladder stairs installed yet. My huband has gone up to get the clothes in rubbermiads stored up there but there isn't a light and you can't stand up all the way in some parts....it is a Colonial type house built in 1965.

 

[Chemist1961]

It is doubtful original venting from 1965 would be adequate today. There is a correct ratio of soffit to rooftop venting based on surface area and roof pitch. There is a requirement for unobstructed air to flow through from your soffits between your rafters and carry hot air to the rooftop venting, year round. This is usally improved with a liner between attic joist spaces which works as a duct flowing upward from the soffit area.
As Scuba says a properly vented roof eliminates most of this heat and humidty build up. I have been in attics in summer that are too hot to work in because of improper vevtilation. If the heat cannot vent up it will travel down to the upper level of your home.
Is the main floor cooler than the upstairs in mid summer? If so the trapped attic heat is radiating down. Check your attic insulation and venting. I had my roof reshingled and venting increased and the upper floor is much more comfortable in the heat of summer. The previous shingles were baked, partly due I'm sure to improper venting
For better understanding of attic ventilation versus regional climate visit www.buildingscience.com